1. Field of the Invention
The present invention relates to actuating devices, e.g., actuating devices in a motor vehicle which have a sensor unit for checking their actuating movement, and also relates to triggering of the actuating devices with the aid of a controller.
2. Description of Related Art
Numerous actuating devices are employed in motor vehicles. The actuating devices normally have actuator units, in order to provide a physical output variable as the actuator value, for example an actuator travel, a valve opening, a temperature or the like. In particular in systems having a combustion engine, the throttle valve actuator, the EGR valve (EGR: exhaust gas recirculation), charge movement flaps and similar components may be named as examples of actuating devices.
The actuator unit of an actuating device normally includes a drive (for example, having a DC motor and a gearbox), which activates a control element, for example the throttle valve in the case of a throttle valve actuator. The actuator units may also include other actuators, however, such as piezoelectric elements.
Furthermore, a sensor unit may be provided, which is coupled with the actuator unit in order to read back the actual position of the control element of the actuator unit. The actual position of the control element is normally used to regulate the output variable of the actuator unit with the aid of a controller, for example an adjustment of the position of a throttle valve in the case of a throttle valve actuator.
For interpretation of the sensor data transmitted to the controller by such an actuating device, it is necessary for the sensor unit to be calibrated, or at least matched to the controller, i.e., for it to provide a corresponding defined sensor value in a digital or analog manner for a particular physical variable to be measured. If the sensor unit of the actuating device is modified or replaced by another type over the operating life of the entire system, the controller may require reprogramming in order to regulate the output variable of the actuator unit as a function of the sensor readings. Since reprogramming of the controller is normally expensive, such an actuating device might have to be produced for decades without changes, so that quality improvements, changing of suppliers and other optimizations are not possible.
The same is also true, of course, if the actuator unit of the actuating device or the actuator unit and the sensor unit of the actuating device are modified or replaced by another type over the operating life of the entire system. In order to provide the same output variable, a modified actuator unit must receive a different control variable, so that here too the controller requires reprogramming when the actuating device is replaced in order to set the desired output variable of the actuator unit.
An object of the present invention is to make an actuating device and a controller available, which allow for a proper triggering of the actuator unit to provide a desired output variable, even if the actuator unit or the sensor unit of the actuating device or the entire actuating device is replaced.
Another object of the present invention is to provide a method that allows for various types of actuating devices to be connected to a controller without a need for reprogramming in the controller.